(1) Field of the Invention
The present invention relates to an image forming apparatus, such as an MFP (Multi functional Peripheral) that has functions of copying, faxing, printing or the like. More particularly, the present invention relates to a technique to efficiently determine a billing amount for a job.
(2) Description of the Related Art
Conventionally, billing operation of an image forming apparatus is performed in such a way that the image forming apparatus downloads and refers to a billing amount table generated by a billing apparatus based on an input by a user.
The billing amount table is a database in which billing amounts are associated with sheet sizes. Upon executing a job, such as copying and printing, the image forming apparatus refers to the billing amount table, and determines a billing amount regarding the job. With this structure, it is possible to charge a fee according to the sheet sizes.
The conventional billing amount tables, however, list the billing amounts in one-to-one association with the sheet sizes. Therefore, the table size increases as the number of available sheet sizes increases. As a result, in the image forming apparatus, the amount of memory to store therein the billing amount table becomes large, and it takes a long time to determine the applicable billing amount based on the billing amount table. Furthermore, downloading of the billing amount table also takes a long time.
The above only describes the billing according to the sheet sizes. When a facsimile function is used, however, it is also conceivable to charge a fee according to telephone numbers. The same problems arise in this case as well.